在Bash 脚本中,检查变量是否包含特定的文本字符串是一个常见的任务。以下是一些基础概念和相关方法: 基础概念 变量:在 Bash 中,变量用于存储数据。 字符串比较:用于检查一个字符串是否包含另一个字符串。 相关优势 简洁性:Bash 提供了内置的字符串操作功能,使得代码更加简洁。
It is used when you want to match everything else that doesn’t match the specified pattern. Let’s have an example where we want to match all the filenames that don’t have the specified pattern. In this example, we match all the filenames that are not text files or Bash scripts....
变量被展开,从展开值的末尾开始匹配PATTERN的最长字符串被删除: $ var=Toronto $ sa "${var%%o*}" :t: ${var#PATTERN}:从开头删除最短的匹配 变量被扩展,匹配PATTERN的最短字符串从扩展值的开始处删除: $ var=Toronto $ sa "${var#*o}" :ronto: ${var##PATTERN}:从开头删除最长的匹配 变量被...
[ken@Desktop]$lsa.txt &&echo"a.txt exists"&&rma.txta.txt a.txt exists[ken@Desktop]$lsa.txt &&echo"a.txt exists"ls: a.txt: No such file or directory[ken@Desktop]$lsa.txt ||echo"a.txt does not exist"ls: a.txt: No such file or directory a.txt does not exist 从上面的示例中...
问GNOME终端bash线包装问题EN设置 组合键 Ctrl + , 打开设置，搜索 Shell: Windows 打开 settings....
pattern2)# commands to be executed if $variable matches pattern2;; *)# commands to be executed if $variable doesn't match any pattern;;esac 示例: #!/bin/bashday="Monday"case$dayinMonday)echo"Today is Monday.";; Tuesday)echo"Today is Tuesday.";; ...
of the operator is considered a pattern and matched according to the rules described below under Pattern Matching. The return value is 0 if the string matches or does not match the pattern, respectively, and 1 otherwise. Any part of the pattern may be ...
The ! operator negates the condition, so it checks if the input does not match the pattern ^[0-9]+$, which means one or more digits from 0 to 9. if (( number % 2 0 )); then ... fi: If the input is a valid number, it checks if the number is even or odd using the ...
Certain characters are special if entered at the beginning of the pattern; they modify the type of search rather than become part of the pattern: ^N or ! Search for lines which do NOT match the pattern. ^E or * Search multiple files. That is, if the search reaches the END of the cu...
-e PATTERN, --regexp=PATTERN Use PATTERN as the pattern; useful to protect patterns beginning with -. -q, --quiet, --silent Quiet; do not write anything to standard output. Exit immediately with zero status if any match is found, even if an error was detected. Also see the -s or ...